علوم زیستی دریا
Zahra Yarahmadi; Bita Archangi; Ahmad Savari; Mohammad Bagher Nabavi
Abstract
The objective of this study was to morphological description and phylogenetic study of Ornithocercus magnificus in Bandar Abbas waters. The genus Ornithocercus is a heterotrophic dinoflagellate of the family Dinophysaceae. The samples were collected using a phytoplankton net (mesh size: 20 µm) ...
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The objective of this study was to morphological description and phylogenetic study of Ornithocercus magnificus in Bandar Abbas waters. The genus Ornithocercus is a heterotrophic dinoflagellate of the family Dinophysaceae. The samples were collected using a phytoplankton net (mesh size: 20 µm) equipped with a flowmeter in surface waters. The plankton samples were scanned and identified with an inverted microscope. Then, the SSU rDNA gene fragment from individual cells have been amplified using the polymerase chain reaction and sequenced for the Iranian strain of this species. Phylogenetic analyzes were performed by Maximum Likelihood (ML) and Maximum parsimony (MP) methods. In this study, two new sequences of SSU rDNA from O. magnificus were reported for the first time and deposited in the GenBank. Morphological studies showed that the isolated cells from Iranian water were O. magnificus. Generally, the results showed; the morphological results of O. magnificus were matched with the molecular results of this study. Phylogenetic analysis grouped isolated Iranian sequences with O. magnificus and formed a monophyletic clad with other members of this genus as sister groups. The genus Histioneis is the closest relative to Ornithocercus.
Abdolali Movahedinia; Zahra Yarahmadi; Sara Rastgar
Volume 11, Issue 3 , November 2012, , Pages 52-62
Sara Sara Rastegar1; Abdolali Movahedinia; Zahra Yarahmadi
Volume 10, Issue 3 , September 2012, , Pages 40-47
Abstract
The present study carried out to assess the effects of Benzo-α-Pyrene (BaP) as a serious member of Polycyclic Aromatic Hydrocarbons (PAH) on the plasma levels of cortisol and triiodothyronine (T3) hormones in male Seabream, Acanthopagrus latus (Sparidea). To assess the acute effects of BaP on the ...
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The present study carried out to assess the effects of Benzo-α-Pyrene (BaP) as a serious member of Polycyclic Aromatic Hydrocarbons (PAH) on the plasma levels of cortisol and triiodothyronine (T3) hormones in male Seabream, Acanthopagrus latus (Sparidea). To assess the acute effects of BaP on the endocrine system, a group of fish was injected with dissolved BaP in sunflower oil (50mg/kg BaP in 2µg/l oil according to the body weight). Other fishes were injected with 2µg/l body weight as controls. Blood samples from both groups collected 3 hours after injection. In another protocol, the chronic effects of BaP on the plasma levels of cortisol and T3 were assessed. For this reason a group of fish was implanted with 50mg/kg BaP in 10µl/g coconut oil in respect to each fish body weight. As the previous protocol a control group was implanted with the same amount of oil without the BaP. Blood samples collected from both implanted groups (treatment and control) after 72 hours. According to the results, plasma levels of cortisol in yellowfin Seabream increased during both short time and long time exposure but T3 levels in the plasma decreased during the chronic stress of BaP exposure. It seems the cortisol levels are elevating to provide more energy requirement under the acute and chronic stress conditions by direct effect on glyconeogenesis and fast blood sugar level to be consumed by cells. T3 levels may be affected by inhibitory effect of Aryl hydrocarbon receptors (AhRs) which decreased it during long term exposure.